1) Field of the Invention
The present invention relates to a monitoring apparatus that monitors a likelihood of an imminent failure of a memory device.
2) Description of the Related Art
Magnetic tape libraries that can store large volumes of data conventionally use magnetic tape cartridges that conform to Linear Tape-Open (LTO) standards or Advanced Intelligent Tape (AIT) standards. A typical magnetic tape cartridge generally has a built-in flash memory such as a Cartridge (CM) or a Memory in Cassette (MIC) for storing various types of management data.
FIG. 7 is a perspective of a conventional magnetic tape library device 1. FIG. 8 is a perspective of a conventional magnetic tape cartridge containing a flash memory. The magnetic tape library device 1 includes a magnetic tape cartridge 2, a magnetic tape drive device 3, and a robot hand 4.
The robot hand 4 pulls out the magnetic tape cartridge 2 from a cartridge cell into which the magnetic tape cartridge 2 is housed and places it in the magnetic tape drive device 3 that writes data to or reads data from the magnetic tape cartridge 2.
Once the data is written to or read from the magnetic tape cartridge 2, the robot hand 4 removes the magnetic tape cartridge 2 from the magnetic tape drive device 3 and places it back in a predetermined place in the cartridge cell.
As shown in FIG. 8, the magnetic tape cartridge 2 has a flash memory 5 built into it. The flash memory 5 stores management data such as location information of data, tracking of usage of the magnetic tape cartridge 2, error log, etc.
The magnetic tape drive device 3 carries out the writing or the reading of the management data. If a read error or a write error occurs, the magnetic tape cartridge 2 is pulled out of the magnetic tape library device 1 and placed in another magnetic tape drive, which then reads the management data from the flash memory 5 to analyze why read error or write error has occurred.
However, in this method, since the management data is accessed for the first time after a read error or a write error, there is a likelihood that the data stored in the magnetic tape cannot be accessed.
To counter this problem, a device is disclosed in Japanese Patent Laid-Open Publication No. 2002-288906 in which information pertaining to failure arising from a faulty magnetic tape cartridge is stored in the flash memory of the magnetic tape cartridge and the likelihood of future failure is determined by reading this failure information. Another device disclosed in International Publication No. W001/026112 stores information pertaining to read or write conditions of the magnetic tape cartridge and determines the life of the magnetic tape cartridge based on the information.
However, even though it is possible in the conventional technology to determine the likelihood of failure of to the magnetic tape cartridge or determine the life of the magnetic tape cartridge by reading the management data stored in the magnetic tape cartridge, failure of to the magnetic tape drive device cannot be determined.
To be specific, since apart from a failure of the magnetic tape cartridge, a failure of the magnetic tape drive device can also cause read error or write error, there is no method in place for effectively determining the latter.